On Tue, Feb 03, 2026 at 08:08:16PM +0800, Jianping wrote: > > > On 2/2/2026 4:41 PM, Greg KH wrote: > > On Mon, Feb 02, 2026 at 03:13:10PM +0800, Jianping wrote: > > > > > > > > > On 1/16/2026 10:49 PM, Greg KH wrote: > > > > On Thu, Jan 15, 2026 at 04:28:48PM +0800, Jianping Li wrote: > > > > > From: Ekansh Gupta <[email protected]> > > > > > > > > > > The fastrpc_buf_free function currently does not handle the case where > > > > > the input buffer pointer (buf) is NULL. This can lead to a null > > > > > pointer > > > > > dereference, causing a crash or undefined behavior when the function > > > > > attempts to access members of the buf structure. Add a NULL check to > > > > > ensure safe handling of NULL pointers and prevent potential crashes. > > > > > > > > What caller passes in NULL here? I did a quick look, and see where the > > > > callers check this properly if it could be NULL, otherwise it all looks > > > > sane to me. What in-kernel user is causing a crash here? Why not fix > > > > the caller up instead? > > > > > > > > thanks, > > > > > > > > greg k-h > > > > > > It's a saftety coding: to eliminate NULL checks on the caller side, as we > > > do > > > in a lot of other kernel API. > > > > But you do not do that for all functions in the kernel, otherwise the > > kernel would be full of checks that are never hit at all. > To clarify the intention: this change was not triggered by any real crash in > current callers. The motivation came from the v1 review discussion [1], > where it was suggested that a NULL check in fastrpc_buf_free() would allow > simplifying some of the caller paths. > > [1] > https://lore.kernel.org/all/[email protected]/ > > > > > And it was pointed out in the v1 patch discussion that this change was > > > needed: > > > https://lore.kernel.org/all/[email protected]/ > > > > Were the checks removed from the caller side like was asked for? > > Currently, I have placed the check inside the API and removed all the checks > outside the API. > > > > > Also, your changelog makes it sound like this is a real bugfix for > > something, when it is not at all, which is what I object to the most. > > Don't make scary changelogs for things that are not actually happening. > > You are correct. I will modify the commit text that caused the > misunderstanding. >
You should then also drop Cc: stable and Fixes:, as this is no longer a bug fix. And make sure you don't put actual bug fixes after this one in the series (i.e. it probably shouldn't be patch 1/4). Regards, Bjorn > > > > thanks, > > > > greg k-h > >
